TY - JOUR A1 - Bachmann, Barbara A1 - Spitz, Sarah A1 - Schädl, Barbara A1 - Teuschl, Andreas A1 - Redl, Heinz A1 - Nürnberger, Sylvia A1 - Ertl, Peter T1 - Stiffness Matters: Fine-Tuned Hydrogel Elasticity Alters Chondrogenic Redifferentiation JF - Froniers in Bioengineering and Biotechnology N2 - Biomechanical cues such as shear stress, stretching, compression, and matrix elasticity are vital in the establishment of next generation physiological in vitro tissue models. Matrix elasticity, for instance, is known to guide stem cell differentiation, influence healing processes and modulate extracellular matrix (ECM) deposition needed for tissue development and maintenance. To better understand the biomechanical effect of matrix elasticity on the formation of articular cartilage analogs in vitro, this study aims at assessing the redifferentiation capacity of primary human chondrocytes in three different hydrogel matrices of predefined matrix elasticities. The hydrogel elasticities were chosen to represent a broad spectrum of tissue stiffness ranging from very soft tissues with a Young's modulus of 1 kPa up to elasticities of 30 kPa, representative of the perichondral-space. In addition, the interplay of matrix elasticity and transforming growth factor beta-3 (TGF-β3) on the redifferentiation of primary human articular chondrocytes was studied by analyzing both qualitative (viability, morphology, histology) and quantitative (RT-qPCR, sGAG, DNA) parameters, crucial to the chondrotypic phenotype. Results show that fibrin hydrogels of 30 kPa Young's modulus best guide chondrocyte redifferentiation resulting in a native-like morphology as well as induces the synthesis of physiologic ECM constituents such as glycosaminoglycans (sGAG) and collagen type II. This comprehensive study sheds light onto the mechanobiological impact of matrix elasticity on formation and maintenance of articular cartilage and thus represents a major step toward meeting the need for advanced in vitro tissue models to study both re- and degeneration of articular cartilage. KW - Tissue Engineering KW - Chondrogenic Redifferentiation KW - Biomaterials Y1 - 2021 VL - 2020 IS - 8 SP - 373 ER - TY - JOUR A1 - Nürnberger, S. A1 - Schneider, C. A1 - Keibl, C. A1 - Schädl, Barbara A1 - Heimel, P. A1 - Monforte, X. A1 - Teuschl, A. H. A1 - Nalbach, M. A1 - Thurner, P. J. A1 - Grillari, J. A1 - Redl, Heinz A1 - Wolbank, S. T1 - Repopulation of decellularised articular cartilage by laser-based matrix engraving JF - EBioMedicine. N2 - Background: In spite of advances in the treatment of cartilage defects using cell and scaffold-based therapeutic strategies, the long-term outcome is still not satisfying since clinical scores decline years after treatment. Scaffold materials currently used in clinical settings have shown limitations in providing suitable biomechanical properties and an authentic and protective environment for regenerative cells. To tackle this problem, we developed a scaffold material based on decellularised human articular cartilage. Methods: Human articular cartilage matrix was engraved using a CO2 laser and treated for decellularisation and glycosaminoglycan removal. Characterisation of the resulting scaffold was performed via mechanical testing, DNA and GAG quantification and in vitro cultivation with adipose-derived stromal cells (ASC). Cell vitality, adhesion and chondrogenic differentiation were assessed. An ectopic, unloaded mouse model was used for the assessment of the in vivo performance of the scaffold in combination with ASC and human as well as bovine chondrocytes. The novel scaffold was compared to a commercial collagen type I/III scaffold. Findings: Crossed line engravings of the matrix allowed for a most regular and ubiquitous distribution of cells and chemical as well as enzymatic matrix treatment was performed to increase cell adhesion. The biomechanical characteristics of this novel scaffold that we term CartiScaff were found to be superior to those of commercially available materials. Neo-tissue was integrated excellently into the scaffold matrix and new collagen fibres were guided by the laser incisions towards a vertical alignment, a typical feature of native cartilage important for nutrition and biomechanics. In an ectopic, unloaded in vivo model, chondrocytes and mesenchymal stromal cells differentiated within the incisions despite the lack of growth factors and load, indicating a strong chondrogenic microenvironment within the scaffold incisions. Cells, most noticeably bone marrow-derived cells, were able to repopulate the empty chondrocyte lacunae inside the scaffold matrix. Interpretation: Due to the better load-bearing, its chondrogenic effect and the ability to guide matrix-deposition, CartiScaff is a promising biomaterial to accelerate rehabilitation and to improve long term clinical success of cartilage defect treatment. Funding: Austrian Research Promotion Agency FFG ("CartiScaff" #842455), Lorenz Böhler Fonds (16/13), City of Vienna Competence Team Project Signaltissue (MA23, #18-08). Keywords: Cartilage regeneration; Decellularisation; Ectopic animal model; Laser engraving; Mechanical testing; Repopulation. KW - Tissue Engineering KW - Cartilage regeneration KW - Mechanical Testing KW - Decellularization KW - Biomaterials Y1 - 2021 VL - 64 IS - 103196. ER - TY - JOUR A1 - Nürnberger, Sylvia A1 - Schneider, Cornelia A1 - van Osch, Gerjo A1 - Keibl, Claudia A1 - Rieder, Bernhard A1 - Monforte, Xavier A1 - Teuschl, Andreas A1 - Mühleder, Severin A1 - Holnthoner, Wolfgang A1 - Schädl, Barbara A1 - Gahleitner, Christoph A1 - Redl, Heinz A1 - Wolbank, Susanne T1 - Repopulation of an auricular cartilage scaffold, AuriScaff, perforated with an enzyme combination. JF - Acta Biomaterialia KW - Tissue Engineering KW - Decellularization KW - Cartilage Y1 - ER - TY - JOUR A1 - Heinzel, Johannes Christoph A1 - Oberhauser, Viola A1 - Keibl, Claudia A1 - Schädl, Barbara A1 - Swiadek, Nicole V. A1 - Längle, Gregor A1 - Frick, Helen A1 - Slezak, Cyrill A1 - Prahm, Cosima A1 - Grillari, Johannes A1 - Kolbenschlag, Jonas A1 - Hercher, David T1 - ESWT Diminishes Axonal Regeneration following Repair of the Rat Median Nerve with Muscle-In-Vein Conduits but Not after Autologous Nerve Grafting JF - Biomedicines N2 - Investigations reporting positive effects of extracorporeal shockwave therapy (ESWT) on nerve regeneration are limited to the rat sciatic nerve model. The effects of ESWT on muscle-in-vein conduits (MVCs) have also not been investigated yet. This study aimed to evaluate the effects of ESWT after repair of the rat median nerve with either autografts (ANGs) or MVCs. In male Lewis rats, a 7 mm segment of the right median nerve was reconstructed either with an ANG or an MVC. For each reconstructive technique, one group of animals received one application of ESWT while the other rats served as controls. The animals were observed for 12 weeks, and nerve regeneration was assessed using computerized gait analysis, the grasping test, electrophysiological evaluations and histological quantification of axons, blood vessels and lymphatic vasculature. Here, we provide for the first time a comprehensive analysis of ESWT effects on nerve regeneration in a rat model of median nerve injury. Furthermore, this study is among the first reporting the quantification of lymphatic vessels following peripheral nerve injury and reconstruction in vivo. While we found no significant direct positive effects of ESWT on peripheral nerve regeneration, results following nerve repair with MVCs were significantly inferior to those after ANG repair. KW - Tissue Engineering KW - Muscle-In-Vein Conduits KW - Axonal Regeneration KW - Autologous Nerve Grafting Y1 - VL - 2022 IS - 10(8) SP - 1777 ER - TY - JOUR A1 - Strohmeier, Karin A1 - Hofmann, Martina A1 - Jacak, Jaroslaw A1 - Narzt, Marie-Sophie A1 - Wahlmueller, Marlene A1 - Mairhofer, Mario A1 - Schädl, Barbara A1 - Holnthoner, Wolfgang A1 - Barsch, Martin A1 - Sandhofer, Matthias A1 - Wolbank, Susanne A1 - Priglinger, Eleni T1 - Multi-Level Analysis of Adipose Tissue Reveals the Relevance of Perivascular Subpopulations and an Increased Endothelial Permeability in Early-Stage Lipedema JF - Biomedicines N2 - Lipedema is a chronic, progressive disease of adipose tissue with unknown etiology. Based on the relevance of the stromal vascular fraction (SVF) cell population in lipedema, we performed a thorough characterization of subcutaneous adipose tissue, SVF isolated thereof and the sorted populations of endothelial cells (EC), pericytes and cultured adipose-derived stromal/stem cells (ASC) of early-stage lipedema patients. We employed histological and gene expression analysis and investigated the endothelial barrier by immunofluorescence and analysis of endothelial permeability in vitro. Although there were no significant differences in histological stainings, we found altered gene expression of factors relevant for local estrogen metabolism (aromatase), preadipocyte commitment (ZNF423) and immune cell infiltration (CD11c) in lipedema on the tissue level, as well as in distinct cellular subpopulations. Machine learning analysis of immunofluorescence images of CD31 and ZO-1 revealed a morphological difference in the cellular junctions of EC cultures derived from healthy and lipedema individuals. Furthermore, the secretome of lipedema-derived SVF cells was sufficient to significantly increase leakiness of healthy human primary EC, which was also reflected by decreased mRNA expression of VE-cadherin. Here, we showed for the first time that the secretome of SVF cells creates an environment that triggers endothelial barrier dysfunction in early-stage lipedema. Moreover, since alterations in gene expression were detected on the cellular and/or tissue level, the choice of sample material is of high importance in elucidating this complex disease. KW - Tissue Engineering KW - Adipose Tissue KW - Lipedema KW - Endothelial Cells Y1 - VL - 2022 IS - 10(5) SP - 1163 ER - TY - JOUR A1 - Hromada, Carina A1 - Hartmann, Jaana A1 - Oesterreicher, Johannes A1 - Stoiber, Anton A1 - Daerr, Anna A1 - Schädl, Barbara A1 - Priglinger, Eleni A1 - Teuschl-Woller, Andreas H. A1 - Holnthoner, Wolfgang A1 - Heinzel, Johannes Christoph A1 - Hercher, David T1 - Occurrence of Lymphangiogenesis in Peripheral Nerve Autografts Contrasts Schwann Cell-Induced Apoptosis of Lymphatic Endothelial Cells In Vitro JF - Biomolecules N2 - Peripheral nerve injuries pose a major clinical concern world-wide, and functional recovery after segmental peripheral nerve injury is often unsatisfactory, even in cases of autografting. Although it is well established that angiogenesis plays a pivotal role during nerve regeneration, the influence of lymphangiogenesis is strongly under-investigated. In this study, we analyzed the presence of lymphatic vasculature in healthy and regenerated murine peripheral nerves, revealing that nerve autografts contained increased numbers of lymphatic vessels after segmental damage. This led us to elucidate the interaction between lymphatic endothelial cells (LECs) and Schwann cells (SCs) in vitro. We show that SC and LEC secretomes did not influence the respective other cell types' migration and proliferation in 2D scratch assay experiments. Furthermore, we successfully created lymphatic microvascular structures in SC-embedded 3D fibrin hydrogels, in the presence of supporting cells; whereas SCs seemed to exert anti-lymphangiogenic effects when cultured with LECs alone. Here, we describe, for the first time, increased lymphangiogenesis after peripheral nerve injury and repair. Furthermore, our findings indicate a potential lymph-repellent property of SCs, thereby providing a possible explanation for the lack of lymphatic vessels in the healthy endoneurium. Our results highlight the importance of elucidating the molecular mechanisms of SC-LEC interaction. KW - Tissue Engineering KW - peripheral nerve regeneration KW - lymphangiogenesis KW - Schwann cells KW - lymphatic endothelial cells Y1 - VL - 2022 IS - 12, 6 SP - 820 ER - TY - JOUR A1 - Ashmwe, Mohamed A1 - Posa, Katja A1 - Rührnößl, Alexander A1 - Heinzel, Johannes Christoph A1 - Heimel, Patrick A1 - Mock, Michael A1 - Schädl, Barbara A1 - Keibl, Claudia A1 - Couillard-Despres, Sebastien A1 - Redl, Heinz A1 - Mittermayr, Rainer A1 - Hercher, David T1 - Effects of Extracorporeal Shockwave Therapy on Functional Recovery and Circulating miR-375 and miR-382-5p after Subacute and Chronic Spinal Cord Contusion Injury in Rats JF - Biomedicines N2 - Extracorporeal shockwave therapy (ESWT) can stimulate processes to promote regeneration, including cell proliferation and modulation of inflammation. Specific miRNA expression panels have been established to define correlations with regulatory targets within these pathways. This study aims to investigate the influence of low-energy ESWT-applied within the subacute and chronic phase of SCI (spinal cord injury) on recovery in a rat spinal cord contusion model. Outcomes were evaluated by gait analysis, µCT and histological analysis of spinal cords. A panel of serum-derived miRNAs after SCI and after ESWT was investigated to identify injury-, regeneration- and treatment-associated expression patterns. Rats receiving ESWT showed significant improvement in motor function in both a subacute and a chronic experimental setting. This effect was not reflected in changes in morphology, µCT-parameters or histological markers after ESWT. Expression analysis of various miRNAs, however, revealed changes after SCI and ESWT, with increased miR-375, indicating a neuroprotective effect, and decreased miR-382-5p potentially improving neuroplasticity via its regulatory involvement with BDNF. We were able to demonstrate a functional improvement of ESWT-treated animals after SCI in a subacute and chronic setting. Furthermore, the identification of miR-375 and miR-382-5p could potentially provide new targets for therapeutic intervention in future studies. KW - Tissue Engineering KW - ESWT KW - Spinal Cord Injury Y1 - U6 - http://dx.doi.org/https://doi.org/10.3390/biomedicines10071630 VL - 2022 IS - 10(7) SP - 1630 ER -